Recently, to reduce a fuel cost and exhaust gas, an economy-running system (i.e., eco-run system) is developed and put to practical use. The eco-run system automatically stop an engine when the operation of the engine is unnecessary (e.g. at the time of the stop of the vehicle such as signal waiting, train passage waiting, and person waiting), and automatically starts up (i.e., restarts) the engine again when the operation of the engine is necessary.
An indicator for informing a user (e.g. a driver) of the execution of the eco-run when the automatic stop and the restart of the engine (i.e., the eco-run) are executed, and an indicator for informing the user of the inexecution of the eco-run when the eco-run is not executed are equipped with the vehicle in which such an eco-run system is incorporated. The user can confirm whether the eco-run is executed by reference to these indicators (see Reference 1).
Under the present situation, the eco-run system to a private vehicle still does not become popular, and hence an accurate mechanism of the eco-run system is not widely recognized. In general, the eco-run system is strongly recognized as a system automatically stopping the engine when the vehicle becomes a stop condition.
However, in an actual eco-run control, in the case where a shift lever keeps to a drive range (D-range) and the engine automatically stops for example, if all of stop conditions including a stop state of the vehicle (i.e., a vehicle speed is 0 km/h), an off-state of an accelerator (i.e., a state in which the accelerator is not depressed), an on-state of a brake pedal (i.e., a state in which the brake pedal is depressed), a state of non-panic braking (non-sudden braking), a state in which an accumulation amount of electricity of a battery used when the engine stops automatically is equal to or more than a given level, and other states are satisfied, the engine stops automatically.
Therefore, when any one of the stop conditions is not satisfied though the vehicle is in the stop state (i.e., the vehicle speed is 0 km/h), a phenomenon in which the engine does not stop automatically occurs. When such a phenomenon occurs so far, the indicator only indicates that the eco-run is not executed. Therefore, when the user misrecognizes the eco-run as a system which automatically stops the engine if the vehicle is in the stop state, the user doubts why the engine automatically stops though the vehicle is in the stop state. In addition, anxiety that the eco-run control does not function normally is given to the user, and the user misunderstands that the eco-run control has failed.
Accordingly, there has been proposed an eco-run system that displays reasons that cannot automatically stop the engine (i.e., an unsatisfied stop condition) and coping processes to the reasons on a display unit of a vehicle navigation apparatus by the applicant (see Reference 2).
[Reference 1] Japanese Unexamined Patent Publication No. 2001-88580
[Reference 2] Japanese Unexamined Patent Publication No. 2006-273215